Agaric acid, also known as agaricin or 2-hydroxynonadecane-1,2,3-tricarboxylic acid, is an organic

tricarboxylic acid A tricarboxylic acid is an organic carboxylic acid whose chemical structure contains three carboxyl functional groups (-COOH). The best-known example of a tricarboxylic acid is citric acid. Uses Citric acid cycle Citric acid, a type of tricar ...

(

fatty acid In chemistry, particularly in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated or unsaturated. Most naturally occurring fatty acids have an unbranched chain of an even number of carbon atoms, ...

) found in fungi, e.g. ''

Laricifomes officinalis ''Laricifomes officinalis'', also known as agarikon, eburiko, or the quinine conk, is a wood-decay fungus that causes brown heart rot on conifers native to Europe, Asia, and North America, as well as Morocco. The fungus is in the order Polypor ...

''. Its molecular formula is C₂₂H₄₀O₇.

Chemical properties

Agaric acid, as any other

, has an

amphipathic An amphiphile (from the Greek αμφις amphis, both, and φιλíα philia, love, friendship), or amphipath, is a chemical compound possessing both hydrophilic (''water-loving'', polar) and lipophilic (''fat-loving'') properties. Such a compoun ...

character. It means that it has both polar (

hydroxyl In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydro ...

groups) and nonpolar (hydrocarbon chain) sections, and therefore, it is not completely

water-soluble In chemistry, solubility is the ability of a substance, the solute, to form a solution with another substance, the solvent. Insolubility is the opposite property, the inability of the solute to form such a solution. The extent of the solub ...

. It is a

tribasic acid In computer science, ACID ( atomicity, consistency, isolation, durability) is a set of properties of database transactions intended to guarantee data validity despite errors, power failures, and other mishaps. In the context of databases, a sequ ...

, and therefore, it can donate up to 3 hydrogen ions to other bases in an acid-base reaction. Other examples of tribasic acids are

phosphoric acid Phosphoric acid (orthophosphoric acid, monophosphoric acid or phosphoric(V) acid) is a colorless, odorless phosphorus-containing solid, and inorganic compound with the chemical formula . It is commonly encountered as an 85% aqueous solution, w ...

citric acid Citric acid is an organic compound with the chemical formula HOC(CO2H)(CH2CO2H)2. It is a colorless weak organic acid. It occurs naturally in citrus fruits. In biochemistry, it is an intermediate in the citric acid cycle, which occurs in ...

. It is an

odorless The sense of smell, or olfaction, is the special sense through which smells (or odors) are perceived. The sense of smell has many functions, including detecting desirable foods, hazards, and pheromones, and plays a role in taste. In humans, it ...

and tasteless acid, and we can also distinguish it by its white color. Its

melting point The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depen ...

at atmospheric pressure is 140 °C.

Molecular structure

Agaric acid is a type of fatty acid that is composed by a long hydrocarbon chain ("tail") and three carboxylic acid groups at one end ("head"). The hydrocarbon chain has sixteen carbons and thirty four hydrogens. This acid has microcrystalline properties, and therefore, forms small

crystals A crystal or crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macros ...

that can not be seen through the naked eye, but are only visible with an

optical microscope The optical microscope, also referred to as a light microscope, is a type of microscope that commonly uses visible light and a system of lenses to generate magnified images of small objects. Optical microscopes are the oldest design of microsc ...

Functions

Agaric acid is used as an inhibitor of metabolism in several animal experiments. It is shown that this acid prevents the formation of C₂ units from citrate and reduces the availability of citrate for the activation of acetyl-CoA carboxylase. Moreover, it has an important role in the metabolism of lipids, because it influences sterol synthesis. Agaric acid induces the mitochondrial permeability transition by collaborating with adenine nucleotide translocase. It facilitates the efflux of accumulated Ca²⁺, disrupts the potential of the membrane and causes mitochondrial lumps. All of these effects bet on membrane fluidity. It's thought that agaric acid activates the opening of membrane pores due to the union of citrate to ADP transporters. However, a later research showed that N-ethylmaleimide inhibits carboxyatractyloside and agaric acid effects. It was found that this amine restricts the pore opening action of agaric acid, but it does not affect the constraint of ADP exchange by agaric acid.

Medical use

Agaric acid is used in medicine as an anhidrotic agent in order to stop excessive perspiration as it paralyses the nerve terminations in the human body's

sweat glands Sweat glands, also known as sudoriferous or sudoriparous glands, , are small tubular structures of the skin that produce sweat. Sweat glands are a type of exocrine gland, which are glands that produce and secrete substances onto an epithelial sur ...

. For example, it helps to avoid

tuberculosis Tuberculosis (TB) is an infectious disease usually caused by '' Mycobacterium tuberculosis'' (MTB) bacteria. Tuberculosis generally affects the lungs, but it can also affect other parts of the body. Most infections show no symptoms, i ...

patients' frequent night sweats. In addition, when taken in doses from 5 to 15 grams, agaric acid produces vomiting in humans. In the past, agaric acid was used as an irritant, an antidiarrhoeal and a bronchial secretions reducer.

Other uses

Physicians use agaric acid, but it also can be used in many other subjects such as

veterinary Veterinary medicine is the branch of medicine that deals with the prevention, management, diagnosis, and treatment of disease, disorder, and injury in animals. Along with this, it deals with animal rearing, husbandry, breeding, research on nutri ...

and

biochemistry Biochemistry or biological chemistry is the study of chemical processes within and relating to living organisms. A sub-discipline of both chemistry and biology, biochemistry may be divided into three fields: structural biology, enzymology and ...

. In lower animals, this substance depresses the nervous, respiratory and circulatory systems. It has been used as a metabolic inhibitor at the cellular and subcellular level in scientific animal experiments. Agaric acid has also been used as an alpha-glycerophosphate dehydrogenase inhibitor in ''

Crithidia fasciculata ''Crithidia fasciculata'' is a species of parasitic excavates. ''C. fasciculata'', like other species of '' Crithidia'' have a single host life cycle with insect host, in the case of ''C. fasciculata'' this is the mosquito. ''C. fasciculata'' h ...

'', which is a species of parasitic

protist A protist () is any eukaryotic organism (that is, an organism whose cells contain a cell nucleus) that is not an animal, plant, or fungus. While it is likely that protists share a common ancestor (the last eukaryotic common ancestor), the exc ...

References

{{Reflist Fatty acids Tricarboxylic acids